Brickwork

Decorative Tudor brick chimneys. Hampton Court Palace, UK.

Twelfth century temple brickwork. Ayutthaya, Thailand.

Dismantled wall showing brickwork.

Brickwork is masonry produced by a bricklayer, using bricks and mortar. Typically, rows of bricks — called courses — are laid one on top of another to build up a structure such as a wall. Elsewhere, brickwork may have a non-load-bearing function, and may exist for a purpose such as that of finishing the corners of walls with brick quoins, or for finishing door or window openings on a building whose load-bearing structure is made of other materials such as timber or steel. In all cases, wherever the bricks are left fully visible — as opposed to being covered up by plaster or stucco — they are called facing bricks.

The construction industry frequently makes use of brick as a building medium, and examples of brickwork are found right back through history as far as the Bronze Age — the fired-brick faces of the ziggurat of ancient Dur-Kurigalzu in Iraq date from around 1400 BC, and the brick buildings of ancient Mohenjo-daro in Pakistan are from around 2600 BC. Much older examples of brickwork made with dried (but not fired) bricks may be found in such ancient locations as Jericho in the West Bank, Çatal Hüyük in Anatolia, and Mehrgarh in Pakistan; these structures have survived from the Stone age to the present day.

Co-ordination of parts

The co-ordinating principle

Parts of brickwork include bricks, beds and perpends. The bed is the mortar upon which a brick is laid. A perpend is a vertical joint between any two bricks, and is usually — but not always — filled with mortar. The allocated dimensions of these parts are in general co-ordinated so that two bricks laid side by side separated only by the width of a perpend have a width identical with the length of a single brick laid transversely on top of them. An example of a dimensionally co-ordinating metric commonly used for bricks in the UK is 215mm x 102.5mm x 65mm, which is intended to work with mortar beds and perpends of a uniform 10mm. There are many other brick sizes worldwide, and many of them use this same co-ordinating principle.

Three devices for structural stability

A wall is subject to stresses acting vertically and from the side. The design and construction of the wall must take account of the need to withstand these forces, and incorporate the means to do so. If the wall is made of bricks, these considerations may affect — or even determine — the layout of bricks in the wall.

The first of three common strengthening devices is the simple practice of ensuring that perpends do not vertically align in any two successive courses. If this rule is observed, then the weight acting on any brick is distributed across an area that widens with each downwardly successive course.

The second device is the practice of constructing brickwork that is thicker than the width of any of its individual bricks, and of tying together some or all of these bricks into the depth of the wall. If — for example — a wall describing an east-west line is under construction, then bricks oriented to point north-south may be built into the width of the wall, their length spanning two widths of brick and tying the brickwork on the transverse plane. Historically, this was the dominant method for consolidating the transverse strength of walls.

The third of three common strengthening devices has become almost ubiquitous in brickwork since the advent of the cavity wall during the mid nineteenth century. A cavity wall comprises two totally discrete walls — each one of which is called a leaf. A cavity separates the two leaves so that there is no masonry connection between them at all. Typically the main loads taken by the foundations are carried there by the inner leaf, and the major functions of the external leaf are to protect the whole from weather, and to provide a fitting aesthetic finish. Although the two leaves may not share the structural load, their transverse rigidity still needs to be guaranteed, and must come from some source other than interlocking bricks. The device used to satisfy this need is the insertion at regular intervals of wall ties into the cavity wall’s mortar beds.

There is a variety of arrangements for the cutting and layout of bricks utilising one or more of these methods for stabilising brickwork. These arrangements may generate anything from a wall of a single leaf with staggered perpends, to more substantial brickwork combining the vertical staggering of perpends with a transverse reinforcement through the wall. Any such arrangement is called a bond.

Thickness

The thickness of brickwork is usually measured in bricks. Brickwork is said to be one brick thick if it has a total width equal to the length of one of its regular component bricks. Accordingly, a wall of a single leaf is a wall of one half brick thickness; a double leaf wall is said to be one brick thick, and so on. The thickness specified for a wall is determined by such factors as damp proofing considerations, whether or not the wall has a cavity, load-bearing requirements, and expense. Wall thickness specification has proven considerably various, and while some non-load-bearing brick walls may be as little as half a brick thick, others brick walls will be much thicker. The Monadnock Building in Chicago — for example — is a very tall masonry building, and has load-bearing brick walls nearly two metres thick at the base. The majority of brick walls are however usually between one and three bricks thick. At these more modest wall thicknesses, distinct patterns have emerged allowing for the judicious layout of bricks internal to the brickwork of each particular specified thickness of wall.

Orientation of a brick

Six positions

A brick is given a classification based on how its face is oriented relative to the face of the finished wall.

• Stretcher: A brick laid with its long narrow side exposed.
• Header: A brick laid flat with its width at the face of the wall, or parallel to the face of the wall.
• Soldier: A brick laid vertically with the long narrow side of the brick exposed.
• Sailor: A brick laid vertically with the broad face of the brick exposed.
• Rowlock: A brick laid on the long narrow side with the short end of the brick exposed.
• Shiner: A brick laid on the long narrow side with the broad face of the brick exposed.

Cut of a brick

The practice of laying uncut full sized bricks wherever possible gives brickwork its maximum possible strength. Occasionally though a brick must be cut to fit a given space, or to be the right shape for fulfilling some particular purpose such as generating a lap by a quoin brick.

• Quarter bat: A brick cut to a quarter of its length.
• Half bat: A brick cut in half across its width.
• Three-quarter bat: A brick cut to three-quarters of its length.
• Queen closer: A brick cut in half down its length.
• King closer: A brick with one corner cut away, leaving one header face at half its standard width.

Bonds

Bonds with courses of mixed headers and stretchers

• 
  Flemish bond
• 
  Monk bond
• 
  A raking Monk bond
• 
  Flemish Garden Wall bond
• 
  Flemish Diagonal bond

Flemish bond

This bond has one stretcher between every header, with the headers centred over the stretchers in the course below.

Double Flemish bond layout patterns

Overhead plan for alternate courses of one brick’s thickness. Bricks visible from a street running east-west are highlighted; queen closers are shown in yellow.

Overhead plan for alternate courses of one and a half bricks’ thickness. Bricks visible from a street running east-west are highlighted; a three-quarter bat is shown in green, queen closers are in yellow.

Overhead plan for alternate courses of three bricks’ thickness. Bricks visible from a street running east-west are highlighted; three-quarter bats are shown in green, queen closers are in yellow.

East-west elevation for the wall of one and a half bricks’ thickness.

Where a course begins with a quoin stretcher, the course will ordinarily terminate with a quoin stretcher at the other end. The next course will begin with a quoin header; at this point the regular run of alternate header and stretcher is broken, and the second brick to be laid in this course is not a stretcher, but is instead a queen closer. The queen closer acts as an offset for the third brick along — which will be a stretcher — aligning this stretcher’s centre above that of the header below, and thus generating the bond. This course then resumes its paired run of stretcher and header, until the final pair is reached, whereupon a second and final queen closer is inserted as the penultimate brick, mirroring the arrangement at the beginning of the course, and duly closing the bond.

Some examples of Flemish bond incorporate stretchers of one colour and headers of another. This effect is commonly a product of treating the header face of the heading bricks while the bricks are being baked as part of the manufacturing process. Some of the header faces are exposed to wood smoke, generating a grey-blue colour, while other simply vitrified until they reach a deeper blue colour. Some headers have a glazed face, caused by using salt in the firing. Sometimes Staffordshire Blue bricks are used for the heading bricks.

Courses of one brick’s thickness

By simply placing stretchers immediately to the rear of the face stretchers, Flemish bonded brickwork with a thickness of one brick is built.

Courses of one and half bricks’ thickness

Alternately, facing bricks and the bricks behind the facing bricks may be laid in groups of four bricks and a half-bat. The half-bat sits at the centre of the group and the four bricks are placed about the half-bat, in a square formation. These groups are laid next to each other for the length of a course, making brickwork one and a half bricks thick.

To preserve the bond, it is necessary to lay a three-quarter bat instead of a header following a quoin stretcher at the corner of the wall. This fact has no bearing on the appearance of the wall; the choice of brick appears to the spectator like any ordinary header.

Courses of two bricks’ thickness

For a still more substantial wall, a header may be laid directly behind the face header, a further two headers laid at 90° behind the face stretcher, and then finally a stretcher laid to the rear of these two headers. This pattern generates brickwork a full two bricks thick.

Single and Double Flemish bond

All these arrangements are forms of Double Flemish bond, so called because the brickwork appears as Flemish bond from both the front and the rear. If bricks are arranged such that those at the rear do not have this pattern, then the brickwork is said to be Single Flemish bond.

Monk bond

This bond has two stretchers between every header with the headers centred over the perpend between the two stretchers in the course below in the bond’s most symmetric form.

Monk bond variations

New Malden Library, London.

Gamla posten. Arvika, Sweden.

Monk bond in Solna, Sweden.

Pyramids highlighted.

In this form, the lap of the bond may be generated by using queen closers. On a wall with a typically right angled corner, a queen closer is placed next to a quoin stretcher. A header, is then laid as the third brick, and with this, the regular run of two stretchers and one header follows on along the course. On the next course up — but at 90° around the corner of the wall — a quoin stretcher is laid first, and then a grouping of a header sandwiched between two queen closers is laid next to the quoin stretcher. After the second of the two queens closers, the usual run of two stretchers and a header is laid along the course.

Raking Monk bonds

Monk bond may however take any of a number of arrangements for course staggering. The disposal of bricks in these often highly irregular raking patterns can be a challenging task for the bricklayer to correctly maintain while constructing a wall whose courses are partially obscured by scaffold, and interrupted by door or window openings, or other bond disrupting obstacles. If the bricklayer frequently stops to check that bricks are correctly arranged, then masonry in a raking Monk bond can be expensive to build.

Occasionally, brickwork in such a raking Monk bond may contain minor errors of header and stretcher alignment some of which may have been silently corrected by incorporating a compensating irregularity into the brickwork in a course further up the wall. In spite of these complexities and their associated costs, the bond has proven popular in the north of Europe.

Raking courses in Monk bond may — for instance — be staggered in such a way as to generate the appearance of diagonal lines of stretchers. One method of achieving this effect relies on the use of a repeating sequence of courses with back-and-forth header staggering. In this grouping, a header appears at a given point in the group’s first course. In the next course up, a header is offset one and a half stretcher lengths to the left of the header in the first course below, and then in the third course, a header is offset one stretcher length to the right of the header in the middle course. This accented swing of headers, one and a half to the left, and one to the right, generates the appearance of lines of stretchers running from the upper left hand side of the wall down to the lower right. Such an example of a raking Monk bond layout is shown in the New Malden Library, Kingston upon Thames, Greater London.

Another pattern sets a header at a given point in a first course. A header in the second course is staggered in the horizontal plane by a length of three-quarters of a stretcher to the right. With each ascending course, the interval of the stagger of headers increases by a length of half a stretcher until the stagger is equal to a length of one and three-quarters of a stretcher. This progression is then reversed so that the stagger then decreases in each ascending course by a half stretcher until it is back down to the length of three-quarters of a stretcher of stagger. This arrangement is repeated as the wall ascends, generating a subtle appearance of indented pyramid-like diagonals. Every two courses gained in height the indented pyramids flip around in the horizontal plane so as to form pyramids that are mirror images of those below. Such a bond appears in the wall pictured left of St Martins Road, Solna Municipality, Sweden.

Many other particular adjustments of course alignment exist in Monk bond, generating a variety of visual effects which differ in detail, but often having the effect of directing a viewing eye diagonally down the wall.

The great variety of Monk bond patterns allow for many possible layouts at the quoins, and this particular is variously planned and executed. A quoin brick may be a stretcher, a three-quarter bat, or a header. Queen closers may be used next to the quoins, but the practice is not mandatory.

Sussex bond

This bond has three stretchers between every header, with the headers centred above the midpoint of three stretchers in the course below.

The bond’s horizontally extended proportion suits long stretches of masonry such as garden walls or the run of brickwork over a ribbon window; conversely, the bond is less suitable for a surface busy with features, such as a Georgian façade. The relatively infrequent use of headers serves to make Sussex bond one of the less expensive bonds in which to build a wall, as it allows for the bricklayer to proceed speedily with run after run of three stretchers at a time.

Flemish Stretcher bond

Flemish Stretcher bond seperates courses of alternately laid stretchers and headers, with a number of courses solely comprised of stretchers. Brickwork in this bond may have between one and four courses of stretchers to one course after the Flemish manner. The courses of stretchers are often but not always staggered in a raking pattern.

Flemish Diagonal bond

Flemish diagonal bond comprises a complex pattern of stretcher courses alternating with courses of one or two stretchers between headers, at various offsets such that over ten courses a diamond-shaped pattern appears.

Bonds with one stretching course per heading course

• 
  English bond
• 
  3D representation of English bond
• 
  English bond, The Old College, Tattershall
• 
  English Cross bond
• 
  Double English Cross bond

One of the two kinds of course in this family of bonds is called a stretching course, and this typically comprises nothing but stretchers at the face from quoin to quoin. The other kind of course is the heading course, and this usually consists of headers, with two queen closers — one by the quoin header at either end — to generate the bond.

English bond

An English bond layout.

Overhead plan for alternate courses of two bricks’ thickness.

The east-west wall, pedestrian’s perspective. Queen closers in yellow.

This bond has alternating stretching and heading courses, with the headers centred over the midpoint of the stretchers, and perpends in each alternate course aligned. Queen closers appear as the second brick, and the penultimate brick in heading courses. A muted colour scheme for alternate headers is sometimes used in English bond to lend a subtle texture to the brickwork. Examples of such schemes include blue-grey headers among otherwise red bricks — seen in the south of England — and light brown headers in a dark brown wall, more often found in parts of the north of England.

English Cross bond

English Cross bond is repeating sequence of four courses. Courses one and three are identical with the heading courses found in the standard English bond. Courses two and four are stretching courses, but these courses are not identical. One of the stretching courses — say course number two — is identical with the stretching course in the standard English bond, consisting of stretchers only, from quoin to quoin. The other course — course number four in this case — also consists of stretchers, but these are staggered relative to the other course of stretchers in the group. The stagger is acheived by placing a header next to the two quoin stretchers in a the course. The bond is widely found in Northern France, Belgium and Holland.

Dutch bond

This bond is exactly like English Cross bond except in the generating of the lap at the quoins. In Dutch bond, all quoins are quarter bats, and no use whatever is made of queen closers.

Double English Cross bond

Comprises two layers of headers (half off-set from one another) followed by two layers of stretchers (quarter off-set from one another). By off-setting the stretchers from each other by one-quarter, perpends in the upper courses of stretchers are aligned with perpends in the upper courses of headers, whereas perpends in the lower courses of stretchers are aligned with perpends in the lower courses of headers.

Bonds with more than one stretching course per heading course

• 
  English Garden Wall bond
• 
  Scottish Bond
• 
  Common or American bond, 5th Ave, Harlem, New York

English Garden Wall bond

A repeating sequence of three courses of stretchers followed by a course of headers, with a queen closer as the penultimate brick at either end the heading course. The heading course in English Garden Wall bond sometimes features bricks of a different colour to its surrounding stretchers. In English chalk districts, flint is substituted for the stretchers, and the headers constitute a lacing course.

Scottish bond

A repeating sequence of five courses of stretchers followed by a course of headers.

American bond

This bond has courses of stretchers and courses of headers, but the ratio of stretching courses to heading courses may vary. Often the ratio is of one course of headers to five courses of stretchers, but can sometimes run to a ratio as high as nine courses of stretchers to one course of headers.

The brick Clarke-Palmore House in Henrico County, Virginia, has a lower level built in 1819 described as being American bond of three to five stretching courses between each heading course, and an upper level built in 1855 with American bond of 6 to 7 stretching courses between each heading course.

Bonds with only stretching courses or only heading courses

• 
  Stretcher bond
• 
  3D representation of cavity wall-stretcher bond
• 
  Stretcher bond, modern brickwork
• 
  Raking Stretcher bond
• 
  Header bond

Stretcher bond

Or Running bond, consists of courses of stretchers, with bricks in each successive course staggered along by a length of half a stretcher. It is the simplest repeating pattern, and will create a wall only one-half brick thick. Such a thin wall is not stable enough to stand alone, and must be tied to a supporting structure. This practice is common in modern buildings, where stretcher bonded brickwork may be the outer face of a cavity wall, or the facing to a timber or steel-framed structure.

Raking Stretcher bond

Courses of stretchers where perpends either do not align at all, or where they align in some pattern other than that of standard stretcher bond.

Header bond

Consists entirely of courses of headers, with the bricks in each new course being staggered by half a header. A three-quarter bat serves for a quoin in alternate courses, generating the necessary offset. Header bond is often using on curving walls with a small radius of curvature. In Lewes, Sussex many small buildings are constructed in this bond, using blue coloured bricks and vitrified surfaces.

Bonds with courses of mixed stretchers and soldiers

• 
  Single Basket Weave bond
• 
  Double Basket Weave bond
• 
  90° Herringbone bond
• 
  45° Herringbone bond
• 
  45° Herringbone bond, Canterbury, UK

Single Basket Weave bond

A row of Single Basket Weave bond comprises pairs of soldiers laid side-by-side, capped with a stretcher, alternating with pairs of soldiers laid side-by-side sat atop a stretcher. Subsequent rows are identical and aligned with those above.

Double Basket Weave bond

A row of Double Basket Weave bond comprises pairs of stretchers laid atop one another, alternating with pairs of soldiers laid side-by-side. The following row is off-set so the pair of stretchers sits below the pair of soldiers in the row above. This results in bricks arranged in pairs in a square grid so that the join between each pair is perpendicular to the join of the four pairs around it.

Herringbone bond

The Herringbone pattern is made by placing a soldier to one side of a stretcher making an ‘L’ shape, then repeatedly nesting further such combinations. Herringbone is sometimes used as noggins in timber framed buildings. The pattern is sometimes rotated by 45°.

Bonds using rowlocks and shiners

• 
  Rat-trap bond

Rat-trap bond

Rat-trap bond substantially observes the same pattern as Flemish bond, but consists of rowlocks and shiners instead of headers and stretchers. This gives a wall with an internal cavity bridged by the rowlocks, hence the reference to rat-traps.

Dearne’s Bond

This bond consists of a course of shiners followed by a course of headers.

Bonds build around square fractional-sized bricks

• 
  Pinwheel bond
• 
  Della Robia bond

Pinwheel bond

Pinwheel bond is made of four bricks surrounding a square half-brick, repeated in a square grid.

Della Robbia bond

A pattern made of four bricks surrounding a square brick, one-quarter the size of a half-brick. It is designed to resemble woven cloth.

Diapering

Brickwork formed into a diamond pattern is called Diapering.

Damp Proof Courses

Moisture may ascend into a building from the foundation of a wall or gain ingress into a building from a wet patch of ground, where it meets a solid wall. This manifest result of this process is called damp. One of many methods of resisting such ingresses of water is to construct the wall with several low courses of dense engineering bricks such as Staffordshire blue bricks. This method of damp proofing appears as a distinctive navy blue band running around the circumference of a building. The efficacy of this means of keeping out damp is more limited by the permeability of the mortar bedding and perpends joining the bricks, than by that of the bricks themselves.

See also

• Ceramic building material
• Construction
• Masonry
• Tuckpointing